JPS6212887B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic focusing interchangeable lens.

A camera that performs automatic focus adjustment by providing a focus adjustment device on the camera body side, connecting the lens barrel of an interchangeable lens connected to the camera to the focus adjustment device, and driving the lens from the camera side. Proposed. Such cameras are required to be capable of not only automatic focus adjustment (AF) but also manual (MF) adjustment. For this purpose, a ring corresponding to a conventional distance adjustment ring is required. Generally, the focus adjustment device installed on the camera side is compact in order to make the camera body compact, and the motor that drives the device cannot provide a sufficiently large output. .

Therefore, there are problems such as that the mechanism related to the movement of the lens on the lens side must be designed to move easily.

As a result of various studies regarding such interchangeable lenses, the inventor of the present invention found that unless the lower side of the operating part on the interchangeable lens side is protected in some way, the operator's hand may hit the brake while operating the camera. I discovered that the automatic focus adjustment was not satisfactory. Furthermore, if the photographer does not hold the bottom side of the lens during shooting, stable camera holding will not be possible, so an interchangeable lens that does not impair the autofocus function even if the bottom side of the lens can be held is required.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic focusing interchangeable lens that solves the above problems.

In order to achieve the above object, the automatic focusing interchangeable lens according to the present invention comprises: a fixed barrel provided integrally with a bayonet; a distance adjustment ring rotatably supported on the outer periphery of the base of the fixed barrel; a lens barrel connected to the distance adjustment ring and moved forward and backward within the fixed cylinder as the lens rotates; and a coupling that connects the distance adjustment ring to an automatic focus adjustment drive mechanism on the camera side when the lens is connected to the camera body. and a protective wall provided by extending the lower part of the fixing cylinder to the surface of the distance adjustment ring to prevent an operator's hand or the like from coming into contact with the distance adjustment ring when using the camera. It is structured as follows.

Further, a fixed barrel provided integrally with the bayonet, a distance adjustment ring rotatably supported on the outer periphery of the base of the fixed barrel, and connected to the distance adjustment ring,
a lens barrel that is moved forward and backward within the fixed barrel as the lens rotates; an aperture preset ring provided in front of the lens barrel and connected to an aperture mechanism within the lens barrel;
an automatic focus adjustment coupling means for connecting the distance adjustment ring to an automatic focus adjustment drive mechanism on the camera side when the lens is coupled to the camera body; a transmission member for transmitting the position of the preset ring to the camera side; and the fixed barrel. and a protective wall with a lower portion thereof extending to the surface of the distance adjustment ring and the front aperture preset ring, so that the operator's hand, etc. comes into contact with the distance adjustment ring and the preset ring when using the camera. It can also be configured to prevent this.

That is, in the interchangeable lens according to the present invention, the movable ring is rationally arranged with respect to the fixed barrel, and the fixed barrel is used to form a protective wall, thereby solving problems in camera operation.

The present invention will be described in more detail below with reference to the drawings and the like.

FIG. 1 is a sectional view showing a first embodiment of a lens according to the present invention.

The lens according to this embodiment is of a type that is coupled to a camera using a bayonet mount, and automatic focus adjustment is performed by an output from a drive mechanism on the camera body side. Manual adjustments are made by manually rotating the distance ring. A fixing member 2 is fixed with a screw to a bayonet mount 1 for fixing the AF lens to the camera. The screw provided inside the fixing member 2 is threadedly engaged with the outer screw of the helicoid ring 2, and serves as a second helicoid. An outer cylinder 2 is screwed to the fixed member 2 on the front side. The inner thread of the helicoid ring 7 is screwed into the lens barrel 8 forming the aperture barrel, and the first
Acts as a helicoid. The lead of the first helicoid is larger than the second helicoid. For example, when f=50 mm, the ratio is 12/0.75=16. A linear key fitting 31 is screwed to the fixing member 3 and fitted into the groove 8b of the lens barrel 8. The distance ring 6 is fitted on the outside of the fixing member 2.
The fixing member 2 is provided with a notch in the circumferential direction corresponding to the movable range of the distance ring 6, and a protrusion 6a facing inward of the distance ring 6 is inserted into the portion 6a, which is connected to the camera body side. A distance ring drive pin 61 that receives a driving force for focus adjustment is screwed. The protrusion 6a is a notch 7a of the helicoid ring 7.
The distance ring 6 and the helicoid ring 7 rotate together. Movement of the distance ring 6 in the longitudinal direction is restricted by the bayonet mount 1 and the outer cylinder 3.

Bayonet mount 1 has automatic aperture lever 10
is rotatably supported, and this automatic aperture lever 10 is biased in the aperture direction by a spring (not shown). One side 10a of the automatic aperture lever 10 extends toward the lens barrel and engages with an aperture blade mechanism, and the other 10b extends toward the camera body and can engage with an aperture control mechanism on the camera body side. When the lens is connected to a camera and before the camera is released, the pin 10b is pushed in the opening direction by a lever on the camera body against the biasing force in the closing direction to maintain the opening state. When the release is performed on the camera side, photometry is performed, and according to the photometry value, the lever of the camera body is driven, and the lever 10b is driven and brought to a suitable aperture position. When exposure is complete, the lever on the main body returns to its original position and the aperture opens.

Similar to the portion 10b of the aperture lever, a distance drive pin 61 extends toward the main body via a decorative plate 4 fixed to the bayonet mount 1 with screws. The lens barrel 8 supports the front group and rear group lenses so as to sandwich the aperture blade mechanism therebetween. A distance scale is provided on the surface of the distance ring 6, and the outer cylinder 3
A depth of field scale is provided on the surface of the camera. Manual focus adjustment (MF) can be achieved by rotating this distance ring 6 by hand, and the pin 6 can be adjusted manually from the camera body side.
Automatic focus adjustment MF is performed by rotating 1.

When the distance ring 6 in either case rotates, the helicoid ring 7 rotates as a unit because the 6a and 7a parts are connected. At this time, due to the second helicoid action between the helicoid ring 7 and the fixing member 2, the helicoid ring 7 moves in the optical axis direction, albeit slightly. This rotation of the helicoid ring 7 is also transmitted to the lens barrel 8. Straight key fitting 31 and straight groove 8b of lens barrel 8
Since the rotation of the lens barrel 8 is restricted due to the relationship between the two, the lens barrel is moved in the optical axis direction and focused.

In the AF lens with the above configuration, it is not a problem when adjusting MF, but when the distance ring 6 is driven from the camera side, the distance ring may be touched by the operator's hand or some obstacle may come into contact with it. This will interfere with automatic focus adjustment. The motor used for focus adjustment built into the camera cannot be used with a sufficiently large output due to the housing space, so if some kind of brake is applied, focus adjustment will not be performed smoothly. Therefore, in this embodiment, the lower part 3b of the outer cylinder 3 is extended to wrap around the distance ring 6 to protect the distance ring. It should be noted that this portion 3b only needs to protect the lower side of the lens that is easily touched during normal photography, and is designed to be at least as high as the optical axis in order to allow manual operation of the distance ring.

Next, a second embodiment will be described with reference to FIGS. 2 and 3.

The fixing member 2 and the bayonet mount 1 are integrally provided with screws.

The automatic distance adjustment ring 65 is lightly rotatably supported by a steel ball on the outside of the fixed member 2. A gear is provided on the maximum outer periphery of this distance adjustment ring 65, and a small gear 62 is coupled thereto. The pinion provided on the other end side of the shaft that is integrally connected with this pinion is the AF on the camera body side when this lens is connected to the camera body.
It is connected to the drive gear and transmits rotational force from the camera body to the automatic distance adjustment ring 65. The automatic distance adjustment ring 65 is integrally fixed with a screw, and the distance adjustment ring 65 is provided with a distance scale and knurled in a portion other than the distance scale. A portion of the automatic distance adjustment ring 65 on the lower side in FIG. 3 is cut out, and the relay plate 63 is fixed thereto. Relay board 6
3 passes through the fixed member 2 and is connected to the helicoid ring 7, and transmits the rotation of the automatic distance adjustment ring 65 to the helicoid ring 7. The helicoid ring 7 has helicoid threads cut on both the inner and outer peripheries.
The outer periphery is threadedly connected to the fixing member 2 and the inner periphery to the lens barrel 8. A groove in the thrust direction is provided on the outer periphery of the lens barrel 8, and a DC key 21 is fitted into the groove. The rotation of the helicoid ring 7 moves the lens barrel 8 forward and backward in the thrust direction. Note that the DC key fitting 21 extends outside the lens frame,
It also serves as a bearing for a mechanism related to the small gear 62. An aperture blade-related mechanism is provided in the center of the inside of the lens barrel 8, and a front lens portion,
The rear ball part is accommodated. In front of the lens barrel 8, an aperture preset ring 11 is provided with the barrel 8 as an axis, so that movement in the front and back direction is restricted by a nut and only rotation is possible. Aperture preset ring 1
1, a click plate 11a is screwed to the aperture ring stopper 11b. This screw 11b and the convex portion of the aperture index ring 12 restrict the rotation range of the aperture preset ring. Aperture index ring 12
The filter frame is tightened around the name ring 15 so that the index is directly above it. The aperture index ring 12 supports a steel ball so as to be pushed out by a compression spring, and this ball works as a click in cooperation with the aperture click plate 11a of the aperture preset ring. An aperture control pin 11c is fixed to the aperture preset ring 11, and the pin 11c passes through an escape groove provided in the helicoid ring 7 and reaches the inside of the lens barrel 8.

A pin 11d is connected to the pin 11c inside the lens barrel 8, extends rearward substantially parallel to the optical axis, and is connected to an aperture value transmission pin 11e. The aperture value transmission pin 11e is rotatably supported by a bayonet mount and a decorative plate 4. The rotation of the aperture preset ring 11 is 11c, 1
It is transmitted to the camera body via 1d and 11e.
The aperture control pin 11d engages a cam plate of the aperture mechanism inside the lens barrel, and rotation of the aperture preset ring 11 deflects this cam plate. This deviation allows the movement of the bell crank of the aperture mechanism to be controlled to determine the aperture diameter. The fixed member 2 has a fixed outer cylinder 3
is screwed, and a depth of field scale is provided on the top of the fixed outer cylinder 3.

A portion 3c that protects the aperture preset ring 11 and a portion 3b that protects the distance ring 6 are integrally provided at the lower part of the fixed outer cylinder 3 and extend forward and rearward. This protective wall is provided to protect the portion below the height of the optical axis when a lens is attached to the camera and the camera is held horizontally.

The lens according to the present invention described in detail above is provided with an effective protective wall in the lower part of the interchangeable lens,
Since the moving parts are protected, operational problems can be completely solved.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a first embodiment of an automatic focusing interchangeable lens according to the present invention, Fig. 2 is a perspective view showing the second embodiment, and Fig. 3 is a cross-sectional view of the second embodiment. It is a diagram. DESCRIPTION OF SYMBOLS 1... Bayonet mount, 2... Fixed member (tube), 3... Outer tube, 4... Decorative plate, 6... Distance ring, 7... Helicoid ring, 8... Lens tube, 10
...Automatic aperture lever, 11...Aperture preset ring,
12... Aperture value indicator ring, 14... Automatic aperture lever, 15... Name ring, 16... Filter frame.

Claims (1)

[Claims] 1. A fixed barrel provided integrally with the bayonet, a distance adjustment ring rotatably supported on the outer periphery of the base of the fixed barrel, and a distance adjustment ring connected to the distance adjustment ring that moves forward and backward within the fixed barrel as it rotates. a lens barrel that can be attached to a camera body; a coupling means that connects the distance adjustment ring to an automatic focusing drive mechanism on the camera side when the lens is coupled to a camera body; An automatic focusing interchangeable lens having an extending protective wall and configured to prevent an operator's hand or the like from coming into contact with a distance adjustment ring when using the camera.